Effect of MED-TLIF Combined with Percutaneous Pedicle Screw Fixation on Function and Spinal Pelvic Parameters in Patients with Lumbar Spondylolisthesis

Background . Lumbar spondylolisthesis is a common clinical spinal lesion. The upper vertebral body of the patient is displaced relative to the lower vertebral body, causing spinal instability and nerve compression. The clinical manifestations are low back and leg pain, abnormal lower limb sensation, and intermittent rupture. In severe cases, cauda equina syndrome and paraplegia may occur. Minimally invasive spinal surgery has developed rapidly in recent years and become the preferred treatment for lumbar spondylolisthesis. Objective . The aim of this study is to investigate the clinical eﬀect of minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) combined with percutaneous pedicle screw ﬁxation in the treatment of lumbar spondylolisthesis under microscope. Methods . The clinical and surgical data of 106 patients with lumbar spondylolisthesis treated in our hospital were selected and divided into research group (56 cases) according to surgical methods (MIS-TLIF combined with percutaneous pedicle screw ﬁxation). The other 50 patients were treated with traditional open percutaneous intervertebral foramen fusion (control group). The surgical trauma-related indicators, visual analog pain scale (VAS) scores before and after surgery, modiﬁed Japanese Orthopedic Association low back pain score (JOA), bone graft fusion eﬀect, spinal pelvic parameters, and surgical complications of the two groups were statistically analyzed in detail. Results . The incision length, intraoperative blood loss, operation time, and hospitalization time in the research group were lower than those in the control group, and the diﬀerences were statistically signiﬁcant ( P < 0 . 05). There was no signiﬁcant diﬀerence in the VAS score and JOA score between the two groups before operation ( P > 0 . 05). The VAS score and JOA score of the research group were lower than those of the control group on the ﬁrst day after operation ( P < 0 . 05). There was no signiﬁcant diﬀerence in the VAS score and JOA score between the two groups at 1 month and 3 months after operation ( P > 0 . 05). Six months, 12 months, and 18 months after operation, the bone graft fusion rates in the research group were 42.86%, 73.21%, and 94.64%, respectively, and those in the control group were 40.00%, 68.00%, and 92.00%, respectively, with no signiﬁcant diﬀerence ( P > 0 . 05). There was no signiﬁcant diﬀerence in PI, PT, SS, LL, TK, LSJA, and SVA between the two groups before and 6 months after operation ( P > 0 . 05). At 6 months after operation, the PTand TK values of the two groups were higher than those before operation ( P < 0 . 05), and the SS, LL, LSJA, and SVA values of the two groups were lower than those before operation ( P < 0 . 05). The complication rate of the research group was 3.57%, which was lower than 18.00% of the control group, and the diﬀerence was statistically signiﬁcant ( P < 0 . 05). Conclusion . MIS-TLIF combined with percutaneous pedicle screw ﬁxation in the treatment of lumbar spondylolisthesis has the same eﬀect as traditional open surgery and has the same correction eﬀect for spinal pelvic parameters, but it has the advantages of less trauma and fewer complications.


Introduction
Clinically, patients with mild lumbar spondylolisthesis can be treated with analgesic drugs, physical therapy, epidural injection, and other conservative treatment methods.
However, for patients with moderate to severe lumbar spondylolisthesis, surgical treatment is needed [1]. e traditional open percutaneous intervertebral foramen fusion can fully relieve the pressure and pain, but its incision is large and the range of paravertebral tissue stripping is large, which has a negative impact on postoperative functional recovery [2]. Minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) can complete the decompression and fusion of lumbar spondylolisthesis with the assistance of the disc mirror system. Compared with traditional open percutaneous intervertebral fusion, MIS-TLIF has the advantages of minimally invasive, but its decompression and fusion effect does not have advantages [3]. erefore, MIS-TLIF is often used in combination with pedicle screw fixation. e traditional open pedicle screw fixation through the median approach requires extensive stripping and stretching of the paravertebral muscles for a long time, which may easily lead to neurovascular damage, massive bleeding, muscle necrosis and fibrosis, low back pain, and muscle atrophy [4,5]. Percutaneous pedicle screw fixation is used to treat thoracolumbar fractures, which can effectively avoid tissue and muscle damage, shorten hospital stay, and reduce intraoperative blood loss. Compared with traditional open surgery, percutaneous pedicle screw internal fixation causes fewer complications and is more conducive to rapid postoperative recovery of patients [6][7][8]. erefore, in order to find a better treatment plan and improve the therapeutic effect of patients with lumbar spondylolisthesis, this study used MID-TLIF combined with percutaneous pedicle screw fixation for the treatment of lumbar spondylolisthesis, and observed its clinical effect and its influence on the spinal and pelvic parameters of patients. e report is as follows. e operator was used the C-arm machine to locate and make a transverse incision of about 2 cm at the location to separate the fascia and establish a working channel. Half of the lateral articular process bone was removed and the nucleus pulposus was resected under a microscope. e residual nucleus pulposus and cartilage plate were removed with a scraper. e prepared bone fragments were pushed into the anterior and bilateral intervertebral spaces to expand the intervertebral space. e PEEK anatomical cage was selected and fitted tightly in the middle or slightly anterior of the intervertebral space. Clean, place hemostatic gauze, and exit the working channel. e universal cannulated screw was placed in the same incision, and after the pedicle screw was inserted, the pre-bent rod was placed in the universal groove of the pedicle screw for locking and reduction. e contralateral pedicle screw rod was installed in the same way. e nut was tightened after conforming to the observed position of the C-arm machine. After the local drainage tube was placed, a needle incision was made to complete the operation. e control group was treated with traditional open percutaneous intervertebral foramen fusion. A 10 cm incision was made in the posterior midline of the patient's lumbar spine, which was cut layer by layer to the deep fascia, and blunt dissection was performed to expose the lower lamina of the upper vertebral body, the upper lamina of the lower vertebral body, and the facet joints. e screw was placed at the vertical intersection of the horizontal line of the center of the lumbar transverse process and the lateral border of the superior articular process. Pedicle screws were placed after confirmation by X-ray. e articular process and part of the lamina on the affected side were excised, the nucleus pulposus was removed, the bone graft surface was cleaned, and the fracture particles were filled. A pre-curved titanium rod was mounted on the end of the pedicle screw and fixed. e surgical site was rinsed, a drainage tube was placed, and the incision was gradually closed, covered with a sterile dressing.

Materials and Methods
To prevent infection, patients in both groups were treated with antibiotics within 48 hours after surgery, and the duration of treatment was 24-48 hours. Glycerol fructose and dexamethasone were given to reduce nerve root edema, and nutritional nerve support treatment was given. e drainage tube was removed 2-4 days after operation. To guide patients with lumbar back muscle function exercise, severe activity was avoided.

Observation Indicators and Detection Methods. (1)
Surgical trauma-related indicators in the two groups: incision length, intraoperative blood loss, operation time, and hospital stay. (2) Comparison of visual analog scale (VAS) scores before surgery, 1 day, 1 month, and 3 months after surgery [9]. e VAS scale is a subjective pain perception scale with a maximum score of 10 and a minimum of 0. e higher the VAS score, the more severe the patient's pain. (3) Modified Japanese Orthopedic Association low back pain score (JOA score) [10]. e highest JOA target function score is 29 points and the lowest is 0 points. e lower the patient's JOA score, the more severe the dysfunction. (4) Bone graft fusion rate: the number of successful fusions/total number of people. (5) Spine and pelvis parameters before and after surgery in the two groups: pelvic incidence angle (PI), pelvic tilt (PT), sacral tilt (SS), lumbar lordosis (LL), thoracic kyphosis (TK), lumbosacral angle Joint angle (LSJA), and sagittal balance (SVA). e parameters of spine and pelvis were detected by X-ray film before operation and 6 months after operation. e patients were taken from a standing position, and the knee joint and hip joint were stretched. e full-length and lateral X-ray films of spine were taken. PI: the angle between the vertical dividing line of S1 endplate and the connecting line from the midpoint of S1 upper endplate to the midpoint of hip joint. PT: the angle between the midpoint of the upper endplate to the midpoint of the hip joint and the horizontal vertical line. SS : S1 endplate tangent and horizontal angle. LL : Angle between upper endplate tangent of L1 and lower endplate tangent of L5. TK : Angle between upper endplate tangent of T4 and lower endplate tangent of T12. LSJA: the angle between the upper endplate tangent of L5 and the posterior cortical tangent of S1, and the angle between the lower endplate tangent of L5 and the upper endplate tangent of S1. SVA : Horizontal distance between C7 plumb line and posterior superior sacral angle. All patients were performed by the same group of radiologists under the same X-ray machine.

Statistical
Processing. SPSS 21.0 was used for data processing software. e measurement indexes such as VAS score and JOA score in this study were tested by normal distribution, which were in line with approximate normal distribution or normal distribution, and expressed as (x( ) ± s). e t-test was used for comparative analysis between groups. χ 2 test was used for analysis and comparison of enumeration data. Test level α � 0.05, and P < 0.05 means the difference is statistically significant.

Comparison of General Data between the Two Groups of Patients.
e age, gender, blood pressure, spinal segment distribution, and other basic data of the research group and the control group were statistically analyzed, and the differences between the two groups were not statistically significant (P > 0.05), see Table 1 for details. Table 1 Comparison of general data of two groups of patients.

Comparison of Surgical Trauma Indexes between the Two
Groups. e incision length, intraoperative blood loss, operation time, and hospitalization time in the research group were lower than those in the control group, and the differences were statistically significant (P < 0.05), see Table 2 and Figure 1 for details. Table 2 Comparison of surgical trauma indexes between the two groups (x( ) ± s).

Comparison of the VAS Score and JOA Score between the Two Groups.
ere was no significant difference in the VAS score and JOA score between the two groups before operation (P > 0.05). e VAS score and JOA score of the research group were lower than those of the control group on the first day after operation (P < 0.05). ere was no significant difference in the VAS score and JOA score between the two groups at 1 month and 3 months after surgery (P > 0.05), see Table 3 and Figure 2 for details. Table 3 Comparison of VAS score and JOA score between the two groups (x( ) ± s). Figure 2 Comparison of VAS score and JOA score between the two groups: (A)VAS Score, (B) JOA Scores.  Table 4 for details. Table 4 Comparison of bone graft fusion rate between the two groups (n (%)).

Comparison of Spine and Pelvic Parameters between the Two Groups.
ere was no significant difference in PI, PT, SS, LL, TK, LSJA, and SVA between the two groups before and 6 months after operation (P > 0.05). At 6 months after operation, the PT and TK values of the two groups were higher than those before operation (P < 0.05), and the SS, LL, LSJA, and SVA values of the two groups were lower than those before operation (P < 0.05), see Table 5 for details. Table 5 Comparison of spinal pelvic parameters between the two groups (x( ) ± s).

Comparison of Surgical Complications between the Two Groups.
e complication rate of the research group was 3.57%, which was lower than 18.00% of the control group, and the difference was statistically significant (P < 0.05). See Table 6 for details. Table 6 Comparison of surgical complications between two groups. Figure 3, A is a 56-year-old female patient with lumbar spondylolisthesis had lumbar pain and intermittent claudication. A, B, and C for preoperative X-ray, MRI, CT data, patients were diagnosed as L4 lumbar spondylolisthesis II°. D is the data of percutaneous pedicle screw surgery in the operation, and E and F are the results of review 1 week after the operation. It can be seen that the patient's lumbar spondylolisthesis is effectively corrected and the internal fixation is stable (see Figure 3).

Discussion
Surgical treatment of lumbar spondylolisthesis is aimed at spinal canal decompression, spondylolisthesis reduction, bone graft fusion and fixation to restore the normal sagittal sequence of lumbosacral region, and improve spinal balance and stability. In traditional open percutaneous intervertebral foramen fusion, paravertebral muscles and surrounding soft tissues need to be peeled off. Postoperative complications such as paravertebral muscle fiber scarification, fat liquefaction, and extradural scar can easily occur, resulting in low back pain. Procrastination can evolve into chronic low back pain [11]. e development of microendoscopic technology has greatly reduced the surgical trauma. MIS-TLIF can not only obtain sufficient decompression but also retain more stable structures and reduce the range of stripping paravertebral muscles. Since the surgical channel does not pass through the spinal canal, it has low risk of injury to the spinal environment, dural sac and nerve root, and has the advantages of small trauma, less bleeding and fewer complications [12]. MIS-TLIF combined with percutaneous pedicle screw fixation is completed once, which can simultaneously deal with spinal stenosis, interbody fusion, and fixation [3]. MED combined with percutaneous pedicle screw MIS-TLIF and traditional open TLIF can achieve good clinical results in the treatment of single-segment lumbar spondylolisthesis. e former has more advantages in intraoperative blood loss, postoperative drainage, shortening hospitalization time, and improving early postoperative low back pain [13].     Emergency Medicine International In this study, it was found that compared with the traditional open percutaneous intervertebral foramen fusion treatment, the incision length, intraoperative blood loss, operation time, and hospitalization time of MIS-TLIF combined with percutaneous pedicle screw fixation treatment were lower, and the complication rate was also lower, suggesting that MIS-TLIF combined with percutaneous pedicle screw fixation in the treatment of lumbar spondylolisthesis had minimally invasive advantages such as small trauma, less complications, and rapid recovery, which was basically consistent with the existing research conclusions.
is is due to the application of the MED endoscopic channel layer by layer expansion to the lesion target decompression, do not need to expose too much tissue, complete intervertebral fusion in small space, less damage to the surrounding tissue. Pedicle screw placement only need 2 cm small incision, avoid extensive stripping of paravertebral muscles, no damage to facet joints, joint capsule, resulting in significantly reduced trauma, more conducive to the rehabilitation of patients [14,15]. e pain and activity disorders of patients with lumbar spondylolisthesis were related to the severity of the disease before operation and to the surgical trauma after operation. In this study, the VAS score was used to evaluate the degree of pain in patients. e JOA score was used to evaluate the degree of lumbar dysfunction in patients. It was found that MIS-TLIF combined with percutaneous pedicle screw fixation in the treatment of lumbar spondylolisthesis can reduce the degree of pain and activity disorder on the first day after operation. e degree of pain and activity disorder at 1 month and 3 months after operation and the bone graft fusion rate at 6 months, 12 months, and 18 months after operation were similar between the two groups. It is suggested that MIS-TLIF combined with percutaneous pedicle screw fixation in the treatment of lumbar spondylolisthesis has the same long-term effect as traditional open surgery. MIS-TLIF combined with percutaneous pedicle screw fixation can reduce the pain and movement disorder of patients earlier, and the early curative effect is better.
Spinal pelvic parameters are important parameters for evaluating lumbar diseases. e PI value is relatively stable after skeletal system development and is not related to posture and position. It is often used as an index to evaluate sacral-pelvic balance in clinic. e PI value of patients with lumbar spondylolisthesis was higher. PT, SS will change with posture changes, commonly used to evaluate the spatial location of the pelvis. e greater the LL/TK ratio, the more serious spinal instability. If LSJA is too large or too small, it can affect the mechanical balance of lumbosacral region. LSJA in normal population is negative, and LSJA in patients with lumbar spondylolisthesis becomes positive. SVA reflects the equilibrium state of sagittal plane [16][17][18]. In this study, the abovementioned indicators were detected, and it was found that the PT and TK values of the two groups at 6 months after operation were higher than those before operation. e SS, LL, LSJA, and SVA values were lower than those before operation, and there was no statistical difference between the two groups. e results suggest that MIS-TLIF combined with percutaneous pedicle screw fixation in the treatment of lumbar spondylolisthesis has the same correction effect as traditional open surgery for spinal pelvic parameters.
In summary, MIS-TLIF combined with percutaneous pedicle screw fixation in the treatment of lumbar spondylolisthesis has the same effect as traditional open surgery and has the same correction effect for spinal pelvic parameters, but has the advantages of less trauma and fewer complications.
Data Availability e datasets used in this study are available from the corresponding author upon reasonable request.

Ethical Approval
is study was approved by the Ethics committee of Baoji Hospital of Traditional Chinese Medicine.

Conflicts of Interest
e authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.